Caliper-gage.



No. 634,968. Patented Ont. I7, i899. G. M. VAN VALKENBURG.

GALIPEB GAGE.

(Application filed June 8, 1899.)

(No Model'.)

amnn'r FFtCiE.

GEORGE M. VAN VALKE NBURG, OF FOREST, CANADA.

CAMPER-GAG E.

SPECIFICATION forming part of Letters Patent No. 634,968. dated October 1'7, 1899. Application filed June 8, 1899. Serial No. 719,776. (NomodeL) T0 ctZZ whom it may concern:

Be it known that I, GEORGE M. VAN VAL- KENBURG, a subject of the Queen of Great Britain, residing at Forest, in the Province of Ontario, Canada, have invented certain new and useful Improvements in Caliper-Gages, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention is particularly designed for watchmakers use, and is of that class in which the distance apart between two caliperjaws is indicated by a pointer upon a dial or sector, the graduation of which represents the conventional gage employed to express certain measurements.

The invention consists in the construction, arrangement, and operation of a compound pointer, whereby greater accuracy is obtained in determining the measurement or gage,all as more fully hereinafter described, and shown in the accompanying drawings, in which- Figure 1 isa plan viewof my improved gage. Fig. 2 is a like view showing the gage as in use. Fig. 3 is an enlarged portion of Fig. 1. Fig. 4 is a section on line 4 4, Fig. 1.

A and A are two caliper-jaws formed at the ends-of the short arms of two levers pivotally secured together at E, so that the long arms B C thereof extend upon the same sides with their short arms.

D is a sector-gage secured to the end of the arm B, and F is a point on the arm 0, whereby the latter forms the pointer-arm to indicate the gage or distance between the jaws upon the sector D, a spring G being interposed between the long arms of the levers, all arranged and constructed to operate in a well-known manner. v

My improvement consists in pivotally securing at a upon the pointer O a supplementary lever which has a long arm H, forming an amplifying-pointer, and a short arm I, which has a slot 1), into which engages a guide-pin c. This guide-pin is adj ustably secured upon the gage-sector D by means of a sliding block cl, which at its under side has a guide-lug e engaging into a slotf, formed in the sector, and a clamp-screw g, which has a knurled head, all so arranged that the sliding block may be moved in the slot and secured by the clamping-nut in any desired position.

The amplifying-pointer H points upon a sector J, which is secured to the pointer O, and has two stops g h, which limit the movement of the pointer H thereon.

K is a spring pressing with its free end against the guide-pin c in such manner as to take up any lost. motion which said pin may have in the slot 1).

In practice it will be seen that by this construction the main pointer O can freely move on the sector D when the sliding block is unclamped, so that it can slide freely. In this condition the pointer G indicates the thickness of any article inserted between the caliper-jaws bythe'nnmber of the gage indicated by it on the sector, as in the usual manner. WVhen the sliding block dis, however,clamped fast on thesector D, the movement of the pointer O imparts also movement to the amplifying-pointer H; but the movement of the former is limited by that of the latter, which must movethrough a larger arc of the circle. The sector J is also graduated to indicate gages correspondingly to the sector D, and as the graduation-marks are so much farther apart and can be subdivided they afford greater facility for reading and more accurate determination of the gage.

In the position shown in Fig. 1 the pointer O is 'at zero, and it can be moved from this position only as far as the pointer H can move on the sector J. For indicating the higher gages the block cl must be moved along in the slot.

To make the use of the instrument convenient through its whole range, I preferably mark the graduations on the sector D in groups corresponding to the range of the pointer H on the sector J. Thus, as shown in the drawings, if the sector J indicates six gages the sector D is divided off into groups of six gages. To indicate then, for instance, a gage between twelve and eighteen, the sliding block would have to be set so thatthe pointer 0 indicates 12, (which being a large graduation mark can be done very accurately.) Then by clamping the block d fast in this position theindications between 12 and 18 are shown by the pointer H on the sector J.

Of course thegage on the sector D may be provided only with division-marks for the IOC) groups, and the intermediate indications are then found by the pointer H. In the drawings the sector D is marked off to show a complete scale, and the pointer C indicates the tion two levers pivotally secured together each having a short arm formed with a caliper-jaw and a long arm one of which has asector-gage attached to its free end, and the other one of which forms a pointer for the same, a spring between the two long arms of said levers, a supplementary lever pivotally long arm to which a sector-gage is attached and the other having a short arm with a caliper-j aw and a long arm operating as a pointer for said sector-gage, and a supplementary lever pivotally secured upon said pointer and having a short arm provided with a slot and a long arm constituting an amplifying-pointer, a sector-gage for said amplifying-pointer, and a sliding block having means of adjustably securing it upon the first-named sector-gage and a pin thereon engaging into the slot of the supplementary lever.

3. In a caliper-gage of the character described, the combination With the pointer C and sector-gage D formed with a slot f, of the amplifying-pointer H pivotally secured upon the pointer O and having a short arm provided with a slot 12, the sliding block (I adjustably in the slotfof the sector-gageD, the pin 0 on said sliding block engaginginto the slot Z), the spring K and the amplifying sector-gage J secured to the pointer O.

In testimony whereof I affix my signature in presence of two witnesses. 

